The operation of an electric machine such as a generator for instance is usually accompanied by great heat densities leading to high temperature gradients within the stator. That is, the problem of excessive heat particularly occurring in the area of the stator, namely caused by so called copper losses, has to be encountered. Hence, it is known to provide respective stator arrangements with respective cooling means in order to provide proper cooling of the stator.
Regarding electric machines having a single-layer configuration, cooling means are regularly inserted in the top or bottom part of the respective stator slots prior to or after installation of the respective sets or layers of stator windings. Thereby, the contact surface between the cooling means and the stator windings is limited, thus thermal exchange and cooling performance is comparatively low.
Another approach for providing proper cooling is to integrate the cooling means in the respective sets of stator windings, i.e. the cooling means is disposed within the stator windings. Thereby, large contact surfaces are possible improving thermal exchange and cooling performance. Yet, this principal is considered as constructively complex and may lead to disadvantages especially in cases of failure since the cooling means are hardly to separate from the stator windings.